Monitoring antibiotic resistance levels in the past few years have revealed a trend towards high degrees of bata-laetam resistance in the pathogens commonly associated with ABS (acute bacterial sinusitis). As a result, non-beta-lactam antibacterials must be considered for treatment of infections such as ABS as the efficacy of therapy with beta-lactam antibiotics, such as the penicillins and cepalosporins may be compromised. SB-265805 is a new quinolone antibacterial agent which represents an advantage amount fluoroquinolones. The primary objective is to demonstrate that the clinical efficacy at follow up of oral SB-265805 320mg once daily for seven days is at least as good as oral cefuroxime axetil 250mg twice daily for ten days in the treatment of ABS infections.